Question

the acronym hippo is used to help us remember the reasons species become endangered and/or go extinct. what does the o in hippo stand for? overharvesting oxygen

Explanation:

The acronym HIPPO is used in the context of species endangerment and extinction. The letters stand for Habitat loss, Invasive species, Pollution, Population (human), and Overharvesting. Overharvesting is a recognized threat to species, while oxygen is not a part of this acronym's meaning in this context.

Answer:

Overharvesting